I have my doubts about the durabilty of those powerpoints.
I like to see what type of sliding contacts are used within them, or they just twist the supply cable behind them ?

It's more a sales tactic to make these ppt's look very practical, but I reckon that these ppt's will cause fires or poor contacts, when loaded near their maximum rating for a period of time.
You'll be replacing these every couple of years is my guess.

The product of rotation, excitation and flux produces electricty.